Hoya caudata
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| Hook. f. |
Hoya caudata is a plant of the genus of wax flowers ( Hoya ) of the subfamily of asclepiadoideae (Asclepiadoideae). The species is native to southern Thailand , Malaysia , Singapore and Sumatra (Indonesia).
features
Hoya caudata has thread-like, winding, densely hairy shoots that are 0.25 to 0.5 cm in diameter and can be up to 5 m long. Young shoots are deep red and hairy with bristles, older shoots are green and almost bare. The plant climbs trees, but also rocks. Adventitious roots are formed at the points on the shoots where they are necessary to anchor the plant securely to the substrate. The leaves are sparsely distributed along the shoots and hang down. They are usually opposite, but often only one leaf develops per leaf node , and not all leaf nodes develop leaves at all. The leaves have a short, roughly 6 mm long, coarse hairy stalk that becomes increasingly bald with age. The thick, fleshy, but rigid leaf blades are ovate, oblong-ovate to lanceolate and measure 4 to 15 cm (exceptionally also up to 22 cm) in length and 2.5 to 7 cm in width. Are long pointed at the outer end, the base is heart-shaped. The leaf blades are dark green with a white speckled pattern and often turn red when exposed to direct sunlight. Young leaves are initially hairy, but with increasing age they become bald. The leaf vein is feathery, but hardly pronounced. All parts have a white or yellow milky sap.
The umbel-shaped inflorescence consists of 8 to 10 flowers (8 to 15 flowers) and has a diameter of 5 to 7 cm. It is flat to slightly concave and hangs down. The 3 to 10 cm long, permanent stalk of the inflorescence is relatively thin, curved and hairy downy. The relatively rigid, bare and curved stems of the individual flowers are 0.5 to 3 cm long. The sepals are linear-lanceolate and 0.13 to 0.19 mm long. The hermaphrodite flowers are radially symmetrical and five-fold. The spread out, five-fold corollas have a diameter of 1.3 to 1.5 cm. The petals are fused at the base. The egg-shaped corolla lobes are tailed and pointed, the apices of the lobes are rolled up. The petals are white to pale pink and densely hairy inside. The long, fringed hair is felty.
The staminal corolla lobes are elliptical-egg-shaped with an outer round, deep red or light red process and an inner, pointed, white or dark red process. The whitish extension of the stamens is 2 to 4 mm long and pulled out like a whip.
The pollinia are oblong-cylindrical, 0.5 mm long. The corpuculum measures 0.2 mm in length and 0.1 mm in width. The flattened caudiculae have broad wings and are 0.1 mm long and 0.1 mm wide. The flowers stay open for 7 days (about three days). They have little or no scent or give off a weak, sweet scent and do not produce any nectar.
The smooth follicles are round in cross section, 0.4 cm thick and 7.5 to 10 cm long. Apically they become a little thinner and are slightly striped. The seeds are flattened, 5 mm long and 0.75 mm wide and provided with a tuft of white hair.
The smooth follicles are round with a diameter of 0.4 centimeters and 7.5 to 10 centimeters long.
The number of chromosomes is 2n = 22.
Geographical distribution and habitat
Hoya caudata occurs from southern Thailand , across the Malaysian peninsula to Sumatra and Borneo . There it grows epiphytically on trees and rocks in lowland rainforests.
Taxonomy
Hoya caudata was first described in 1883 by Joseph Dalton Hooker in the "Flora of British India". Synonyms are: Hoya crassifolia Ridley (1912) (nom. Illeg., Art. 53.1) and Hoya flagellata Kerr (1940).
literature
- Christiane Hoffmann, Ruurd van Donkelaar, Focke Albers: Hoya. In: Focke Albers, Ulli Meve (Hrsg.): Succulents Lexicon Volume 3 Asclepiadaceae (silk plants) . Pp. 147-160, Ulmer, Stuttgart 2002, ISBN 3-8001-3982-0 , pp. 149/50.
- Dale Kloppenburg and Ann Wayman: The World of Hoyas - a pictorial guide. A revised version. 248 pp. Orca Publishing Company, Central Point, Oregon, 2007 ISBN 0-9630489-4-5 , pp. 80/81.
- Anthony Lamb, Michele Rodda (with contributions by Linus Gokusing, Steven Bosuang and Sri Rahayu): A Guide to the Hoyas of Borneo. Natural History Publications (Borneo), Kota Kinabalu, 2016 ISBN 978-983-812-170-5 , pp. 50/51.
- Surisa Somadee, Jens Kühne: Hoya 200 different wax flowers. 96 p., Formosa-Verlag, Witten 2011 ISBN 978-3-934733-08-4 , p. 36
- Anders Wennström, Katarina Stenman: The Genus Hoya - Species and Cultivation. 144 p., Botanova, Umeå 2008 ISBN 978-91-633-0477-4 , p. 40.
Individual evidence
- ↑ a b c Michele Rodda and WF Ang: Hoya caudata Hook. f. (Apocynaceae), a new record for Singapore, and keys to the Hoya species of Singapore. Nazure in Singapore, 5: 123–128, 2012 [PDF]
- ↑ Livia Wanntorp: Pollinaria of Hoya (Marsdenieae, Apocynaceae): Shedding Light on Molecular Phylogenetics. Taxon, 56) (2): 465-478, 2007 online at JSTOR
- ↑ a b website of Simone Merdon-Bennack
- ↑ www.myhoyas.com
- ↑ Hoya caudata at Tropicos.org. In: IPCN Chromosome Reports . Missouri Botanical Garden, St. Louis
- ^ Joseph Dalton Hooker: The Flora of British India. vol. 4 Asclepiadeae to Amarantaceae. 780 pp., London 1883 (p. 60) Online at archive.org , p. 60